Golf club head



Nov. 1, 1949 E. P. KEARSLEY ETAL GOLF CLUB HEAD Filed Dec. 20, 1944F7111! Jill/1701M d .1124

INVENTORS BY la a/ Wfm ATTORNEYS V Patented-Nov. l, 1949 UNITED STATESPATENT I OFFICE com onus mean Edward P. Kcarsley, Springfield, andEmil-I. Marciniak, Easthampton, Masa, aosignoro to A. G. Spalding &Bros. Inc., Chico a corporation. of Delaware pee, Mala,

Application December 20, 1944, serial No. 588.955

4 Claims. (cl. era-1'1) successful because the heads did notpossess thefeel and sound of wood and disclosed properties,

' when in use, which rendered the clubs unsatisfactory. Some of theseproperties were failure and breakage under repeated blows caused duringthe use of the club for its intended purpose, inability of the club tomaintain its resiliency so that on a hot day it would become soft andloggy while on a cold day it wouldbe very brittle, beingtoo heavy sothat they had to be bored out to such an extent to bring them down tothe desired weight that they were unsuitable for use, and producing ahigh-pitched unnatural sound when striking a golf ball.

We have discovered that a golf club head of molded nylon overcomes thesedifficulties and produces a head which has a satisfactory appearance,feel and a sound on impact, of a slightly higher pitch than that ofawooden club and which stands up satisfactorily under use particularly inthe thin sections thereof.

Other features and advantages of the invention will become apparent fromthe specification and claims when considered in connection with thedrawings in which:

Figure 1 is a perspective view of the club head.

Fig. 2 is a bottom view of the club head with the sole plate removed.

Fig. 3 is a section of the head taken along the' line 3-3 of Fig. 2.

shaft receiving neck It and a striking face I 2 which is scoredlongitudinally and transversely at 03 as is usual in wooden golf clubsof this character. The bottom of the head may be provided with a recessM as shown in Fig. 2 in which is mounted a sole plate L; which usuallyis formed of metal.

The head is preferably formed of polyamides of adipic acid andhexamethylene diamine or nylon, manufactured and sold by E. I. Du Pontde Nemours & Company of Wilmington, Delaware. The formula of polyamidesof adipic acid and hexamethylene diamin'e is:

it may be molded to substantially its final form by injection molding orother suitable molding processes. The-head can be molded directly on theshaft IE, or the head formed separately with the neck having a shaftreceiving bore l1 into which the shaft is inserted and secured bysuitable adhesive or cement and additionally by means of a screw I 8. Ifthe shaft is to be readily removable, a sleeve, not shown, can be moldedwithin the bore l1 and be provided with means to which the shaft may bereadily detachably connected.

. The material of the head has dimensional stability during the moldingoperation. Very little machining is required to finish the heads andthis may be done readily as the material of the head can be machinedwithout excessive strains being set up therein due to heating up of thematerial.

Nylon has a specific gravity slightly greater than that of wood so thata head of normal size requires but a minimum amount of coring to producesubstantially the same weight as that or an average wooden club. Thecoring maybe done during the molding of the head or by a cutting ordrilling operation after tne head has been molded. As is shown in Figs.3 and 4, the coring results in a small cavity is. This cavityconveniently may receive the usual required weight means 20 which issecured in place by screw 2|.

It has been found that heads made of nylon,

and particularly thin sections thereof, such as are found around theneck and, in sections formed as a result of the above-mentioned coringoi the head, have excellent resistance to impact fatigue and do notrequire reinforcement; By impact fatigue is meant the failure of a headto stand up under successive blows as would be encountered in the use ofa golf club, and to show cracking in the faceand fracture and breakagein the thin sections. 7

We have discovered this property in nylon and so far as we have beenable todetermine, it bears no direct relation to the knowncharacteristics 'of plastic materials such as impact strength,

tensile strength, compression, elongation, and modulus of elasticity.etc.

Because of this characteristic, heads made 0 nylon can be more readilyand cheaply manufactured than prior heads since they do not have to haveany reinforcements molded in them or special means for providing areinforced mounting for the shaft thereto.

The head of the present invention is very hard, abrasive resistant, andhas the advantage that the striking face does not become dented throughimpact with the ball and the scoring thereon does not breakdown as inthe case of a wooden club which must be completely refaced when thisoccurs.

Since the head is very hard, the sole plate may or other means. However,in view of the fact that the sole plates receive the greatest wear andmust be frequently removed for replacement or repair by unscrewing thescrews, it is preferred to mold anchoring members in the head to whichthe screws or other securing means may be connected. The anchoring meansare preferably metal sleeves 22 opening into the sole plate recess andinto' which the screws 23 may be threaded.

The club head of the present invention has an excellent appearanceparticularly because the material of the head takes a high polish. Ithas an advantage over wooden heads however in that it has a highresistance to abrasion. When scratches do occur, they may be covered upby a coat of wax or the like whereas a wooden head would require acomplete new coat of varnish to take them out.

Furthermore. the material of the head maintains its resiliencythroughout the range of usual climatic temperature so that the club doesnot become soft and loggy on hot days and brittle. on cold days. 7

When any golf ball is struck with a wooden club by a player, there is adefinite feel and there is Variations and modifications may be madewithin the scope of this invention and portions of the improvements maybe used without others.

We claim:

1. In a golf club of the "wood type, a head of molded nylon, said headhaving thin walled sections.

2. In a golf club of the "wood type, a head of molded nylon, said headhaving a thin walled shaft-receiving neck.

3. In a golf club of the "wood" type, a head of molded nylon, said headhaving a recess therein forming unreinforced walls of thincross-section.

'4. A golf club head of the wood type of molded nylon, said head havingthin walled sections having great resistance to impact fatigue.

EDWARD P. KEARSLEY. Elm; J. MARCINIAK.

REFERENCES CITED The following references are of record in the I file ofthis patent:

produced a characteristic click or sound which ing a golf ball is soslightly higher in pitch than when the ball is struck by a wooden clubthat theplayer is not conscious of it during play.

UNITED STATES PATENTS 'Number Name 1 Date 745,044 Dunn Nov. 24, 19031,202,383 Hardman Oct. 24, 1916 1,841,062 Schavoir Jan. 12, 19321,864,513 Balch June 28, 1932 2,301,369 Carvill Nov. 10, 1942 2,309,729Gordon Feb. 2, 1943 2,346,617 Schaffer Apr. 11, 1944

